Chapter: To prolong the standing posture in the Tahajjud

`Abdullah said, "One night I offered the Tahajjud prayer with the Prophet (ﷺ) and he kept on standing till an ill-thought came to me." We said, "What was the ill-thought?" He said, "It was to sit down and leave the Prophet (standing)."

Whenever the Prophet (ﷺ) got up for Tahajjud prayer he used to clean his mouth (and teeth) with Siwak.